High flow, hydrogenated styrene-butadiene-styrene block copolymers and applications

ABSTRACT

The invention relates to unique applications for the novel high melt flow, low viscosity, selectively hydrogenated styrene-butadiene-styrene (hSBS) or selectively hydrogenated controlled distribution styrene-butadiene/styrene-styrene (hSBSS) block copolymers, wherein the melt flow rate of said block copolymer is at least 100 g/10 min at 230° C. under 2.16 kg mass according to ASTM D1238. These block copolymers are novel and have the highest melt flow rate of any styrenic block copolymer also possessing high strength and elasticity. It has applications that prior to the present invention were not normally possible due to the normal low melt flow rate of styrenic block copolymers. The present invention also encompasses various fields of use such as a fiberglass hSBS or hSBSS reinforced mat, low viscosity hSBS or hSBSS coatings for industrial uses, hot melt adhesives prepared from hSBS or hSBSS blended with polyalpha-olefins, and elastic film, fiber, and nonwoven constructions using hSBS or hSBSS.

This application is a divisional of U.S. patent application Ser. No.13/404,150 filed Feb. 24, 2012, the contents of which are incorporatedin full by reference herein.

FIELD OF THE INVENTION

The invention relates to high melt flow, low viscosity selectivelyhydrogenated styrene-butadiene-styrene (hSBS, also known as SEBS) orselectively hydrogenated controlled distributionstyrene-butadiene/styrene-styrene (hSBSS, also known as styrene-ethylenebutadiene/styrene-styrene (S-EB/S-S)) block copolymers and applicationstherefore, wherein the melt flow rate is at least 100 g/10 min at 230°C. under a 2.16 kg mass according to ASTM D1238. These block copolymersare novel and have significantly higher melt flow rates than other knownstyrenic block copolymers and also exhibit surprising high strength andelasticity. They have applications that, prior to the present invention,were not possible due to the normally low melt flow rate of styrenicblock copolymers.

BACKGROUND OF THE INVENTION

Melt flow rate (MFR) is inversely correlated to viscosity of thepolymer. A high melt flow rate means that the polymer has a lowviscosity and vice versa. While a few styrenic block copolymers havehigh melt flow rates, they achieve that with a high (>60 wt. %) diblockcontent and therefore have comparatively poor mechanical properties. Thehighest reported melt flow rate for any styrenic block copolymer, in theabsence of additives to lower the viscosity and thus increase the meltflow rate, is 81 g/10 min. (As used herein including the claims, unlessotherwise stated, “melt flow” shall mean the melt flow value determinedaccording to ASTM D-1238, at 230° C. under a 2.16 kg mass.) This meltflow rate is disclosed in the following patent.

U.S. Pat. No. 7,439,301 to Handlin, Jr. relates to coupled blockcopolymers having high melt flow and high elasticity. The true molecularweight for the block copolymer is between 40,000 to 70,000; thepolystyrene content (PSC) is between 13 to 25%, the vinyl content isbetween 60 to 85%, and a coupling efficiency of 89 to 97%.

U.S. Pat. No. 7,169,848 to Bening et al discloses selectivelyhydrogenated controlled distribution hSBSS. The highest MFR in theexamples is 17 g/10 min.

Historically, composite systems have been based on fiberglass mat pliesor layers in addition to a binder. The binder could include non-reactiveor reactive polymeric binder such as polyester, vinyl ester or epoxyresins, or a non-reactive resin such as asphalt or bitumen. Thefiberglass mat plies are commonly used as structural support componentsfor the composite. Composites are often designed to have maximum impactresistance while maintaining low density so that weight can beminimized. Traditional composite designs achieve toughness eitherthrough toughening of the reactive resin through the addition ofdispersed rubber particles that arrest crack growth or through the useof optimized sizings on the glass fibers in order to improve adhesionbetween the glass fibers and the reactive resin binder. Both tougheningmechanisms can also be used simultaneously. Materials that enable newcomposite designs or structures to enhance toughening performance orenable new composite designs or processing techniques, while maintaininglow density, are industrially relevant and desirable. These resins havelong lay-up times as well as long cure times. Due to the volatility ofthese resins, as well as the hazards of loose fiberglass strands, themanufacturing process of traditional composites suffers from adversehealth, safety, and environmental problems. Boat hulls and decks,automotive body panels, and aerospace components are prime exampleswhere these types of composites find utility. Large parts like boathulls and decks are often constructed in outdoor locations, or in areaswhere there is only a roof overhead to allow the fumes to exhaust to theenvironment and lessen exposure to the workers.

Low viscosity coatings using styrenic block copolymers are virtuallyunknown because the copolymers normally have such high viscosity. Oftena balance must be achieved between low volatile organic compounds (VOC),high solids content, and low viscosity. Obtaining a low viscositycoating based on hSBS and hSBSS, so that the coating can be sprayed orroll applied onto a substrate, generally requires the use of higheramounts of organic solvents which adversely increase the VOC content andreduce the solids content. Therefore, styrenic block copolymerspreviously had limited applicability for low viscosity coatings wherethe VOC requirement is ≦350 g/L.

Styrenic block copolymers (SBC) have been employed in the adhesivemarket for hot melt, quick release covering, and pressure sensitiveadhesives. Adhesives made with traditional hSBS (SEBS) are typicallyhigh cost with high performance while those made with traditional SBSare more suited for mid-cost, mid-performance markets. They aretypically unsuitable for low cost adhesive markets or applicationsrequiring low spray temperature of <325° F. Typically metallocenepolyolefins or amorphous poly alpha olefins (APO) are utilized in lowcost, low performance applications but result in lower adhesion strengthand temperature resistance properties, which are important for certainhot melt adhesive applications. U.S. Pat. No. 7,348,376 to Gellesdescribes the combination of low melt flow rate hSBS polymers with APOs.However, these formulations lack the viscosity needed for application atlow spray temperatures of <325° F.

The novel compound of the present invention is different than moreconventional hSBS or controlled distribution hSBSS because it has a veryhigh melt flow rate, a corresponding low viscosity, and good tensilestrength and elasticity. This also makes it possible for such polymersto participate in markets not typically considered, such as tougheningfiberglass, low viscosity-low VOC polymer coatings, adhesives based onblended systems requiring low viscosity for improved processability, andfilm and non-woven personal hygiene applications. Thus there is a needfor high melt flow rate hSBC products that have good performancecharacteristics such as strength and elasticity.

SUMMARY OF THE INVENTION

All ranges set forth in the specification and claims include not onlythe end point of the ranges, but also every conceivable number betweenthe end point of the ranges, since that is the very definition of arange. For example, ranges specifying the molecular weight, polystyrenecontent, vinyl content, coupling efficiency, etc., are intended toinclude this definition of a range.

The present invention encompasses a novel hSBS (S-EB-S) orhSBSS(S-EB/S-S) that possess a high melt flow rate, low viscosity, highstrength, and good elastic properties. In particular, the styrenic blockcopolymer comprises a melt flow rate equal to or greater than 100 g/10min, a minimum linear true peak molecular weight (Mp) of about 45,000, aPSC of between about 18 to about 45%, a vinyl content of about 65 to80%, and a coupling efficiency of about 60 to about 97%, said styrenicblock copolymer having a structure consistent with selectivelyhydrogenated poly(monoalkenylarene-diene-monoalkenylarene), orpoly(mono-alkenylarene-diene)_(n)X, or controlled distributionpoly(monoalkenylarene-diene/monoalkenyl-arene-monoalkenylarene) orpoly(monoalkenylarene-diene/monoalkenylarene)_(n)X. Themono-alkenylarene monomer is preferably selected from the groupconsisting of styrene, alpha-methylstyrene, para-methylstyrene,tertiary-butyl styrene, vinyl toluene and the like or mixtures thereof;of these, styrene is the most preferred. The diene monomer can be anyaliphatic conjugated diene including 1,3-butadiene or substitutedbutadienes such as isoprene or mixtures thereof; of these, 1,3-butadieneis the most preferred. As used herein, and in the claims, “butadiene”refers specifically to “1,3-butadiene”. An hSBS of selectivelyhydrogenated poly(styrene-butadiene-styrene) is also known as S-EB-S,while an hSBSS of selectively hydrogenated controlled distributionpoly(styrene-butadiene/styrene-styrene) is also known as S-EB/S-S. Thesestyrenic block copolymers may be functionalized in a number of ways toinclude reactive groups such as carboxylic acids and their salts,anhydrides, esters, imides, amides, amide and acid chloride groups.

The present invention also encompasses various fields of use, such astoughened fiberglass hSBS or hSBSS reinforced mats for compositeapplications, low viscosity hSBS or hSBSS coatings for industrial uses,hot melt adhesives prepared from hSBS or hSBSS blends with APOs, elasticfilms, melt blown fibers and articles, and low viscosity moldingapplications, such as slush molding, rotational molding, or injectionmolding.

Specifically, coated ceramic or polymeric fibers or bundles of fibersare often used to reinforce polymeric materials and constructions.Fiber-reinforced polymers (FRP) can be of the thermoset or thermoplastictype. When reinforcing thermoset polymers, the fiber reinforcement istypically in the form of a chopped, non-woven, or wet-laid mat or wovenscrim. When reinforcing thermoplastic materials, the fiber reinforcementis typically in the form of chopped fibers either short or long indimension. In order for the ceramic or polymeric fibers to transferstress to the polymer matrix, a sizing or coating is sometimes appliedto the surface of the fibers or bundles of fibers. Many differenttechniques have been developed to coat ceramic or polymeric fibers orbundles of fibers. These techniques may be restricted by high melt orsolution viscosities of the polymeric coatings. As such, low viscosityhSBS or hSBSS or maleated hSBS or hSBSS finds utility as a sizing agentor coating when bonded to the surface of individual ceramic or polymericfibers or bundles of fibers. The terms “ceramic” and “polymeric” fibersinclude but are not limited to glass fiber (or fiberglass), carbonfiber, aramid fiber, and polyester fiber.

Specifically, a fiberglass reinforced mat, comprising: a woven,nonwoven, chopped, or wet laid fiberglass mat or scrim (herein referredto as mat) and an hSBS or hSBSS block copolymer article bonded to saidmat; said hSBS or hSBSS block copolymer having a melt flow rate equal toor greater than 100 g/10 min, wherein when 140 g/m² (grams per squaremeter) of said styrenic block copolymer is applied to said mat, theaverage impact energy is at least 3 times larger than without saidstyrenic block copolymer. The amount of styrenic block copolymer of thepresent invention in a reinforced mat or scrim is about 50 to about 500g/m². Preferably the amount of styrenic block copolymer of the presentinvention in a reinforced mat or scrim is about 50 to about 200 g/m².Such reinforced mats possess an average impact energy of at least 2times, and preferably at least 3 times (or more), than mats without thehSBS or hSBSS block copolymer of the present invention. Maleated hSBS orhSBSS finds utility as a sizing agent when bonded to the surface ofindividual glass fibers. Alternatively, other rigid fibers routinelyused in composite articles, such as carbon fibers, may be used in placeof fiberglass.

Low viscosity coatings containing solvent and styrenic block copolymersof the present invention are primarily used in industrial and marineapplications, in coating metal to prevent corrosion, or concrete toprotect against certain chemical attack, such as oil. Such coatings mayfurther contain a slip-resistant additive, a component making saidcoating removable, such as a protective coating; a corrosion resistantadditive, a shatter-proof additive, a primer additive, or a maintenancecorrosion resistance additive such as iron oxide.

Specifically, a low viscosity hSBS or hSBSS polymer coating formulation,comprising: a blend of solvent and hSBS or hSBSS block copolymer; saidblock copolymer having a melt flow rate equal to or greater than 100g/10 min, wherein said solvent is selected from the class of non-exemptorganic solvents or exempt solvents or mixtures thereof. Exempt solventsinclude: methyl acetate, para-chlorobenzotriflouride, tertiary-butylacetate, or acetone, wherein said blend is at least 50 wt. % solids. Theblend may also contain at least one other ingredient selected from thegroup of endblock resin, midblock resin, polyisobutylene polymers,polyphenylene ether, and/or one or more fillers such as TiO₂, CaCO₃,carbon black, or other pigments, and said coating having a Brookfieldviscosity <150,000 cps as measured by ASTM D2196A. These low viscositypolymer coating formulations may also include reactive monomers such asepoxy, acrylic, styrenic, vinyl-ester, or polyester resin. Such coatingsfind utility in industrial and marine applications. Functionalizedpolymers of the present invention, such as maleic anhydride grafted ontothe backbone of hSBS or hSBSS polymers also find utility in lowviscosity polymer coatings.

Specifically, applications of pure wax are limited due to their brittlenature and poor strength and elasticity. As such, modified waxcompositions comprising the addition of midblock resin(s), additivessuch as EVA or/and PE wax, organic fillers, and hydrogenated styrenicblock copolymers have utility in applications such as investmentcasting, flexible packaging wax (paper/film/foil-based, in-moldlabeling, confectionery wrap, cheese & butter wrap, coffee packaging),hot melt adhesive wax, general industrial wax, cosmetic andpharmaceutical wax (crèmes and ointments, decorative cosmetics,depilatory wax, medical wax) paper and board converting (board & sheetlaminating, multi wall paper bags & sacks, envelopes, security &document bags, tube winding, case & carton, labeling), construction(roof insulation, roofing membranes, sandwich panels), product assembly(strapping, air filters), emulsions, wax coatings, food (chewing gum anddairy), wax extrusion, tire & rubber (tires, technical rubber articles),and other industrial applications. However, even in these areas theability to improve toughness and elasticity of the modified wax has beenlimited by the low melt flow rate (high viscosity) of traditional hSBSpolymers. For example, modification of wax with the addition of KratonG1652 which is considered to be a relatively low molecular weight hSBSis limited to <5% due to the upper viscosity limit for sufficientprocessability.

Suitable midblock resins are C₅ resin (pentadiene resin, pentene, etc.),hydrogenated C₅ resin, terpene resin, rosin ester resin, or combinationsthereof.

Suitable organic fillers are crosslinked polystyrene, bisphenol acid,terephthalic acid or combinations thereof and have a particle size ofless than 200 microns.

High melt flow hSBS polymers of the present invention in blendscontaining microcrystalline wax, polyethylene wax, naphthalene wax,paraffin wax, and less refined wax or combinations thereof are ofinterest in modified wax applications to improve strength, toughness,and elasticity, yet remain sufficiently ridged while maintaining aformulated viscosity of about 2,000-10,000 cps, more preferably3,000-5,000 cps measured via cone and plate rheometry at 140° F. and 50sec⁻¹. Low temperature, impact resistance, lower moisture vaportransmission rate, and improved flex crack resistance are alsobeneficial features that the low viscosity polymers bring to modifiedwax applications. Examples of applications are investment casting wherewax is brittle for large molds or very thin parts. High margininvestment casting molds are used in automotive, aerospace, medical bodyprosthetic replacement (e.g. knee and hip parts), and leisure sports(e.g. golf parts) industries.

High melt flow (low viscosity) hSBS polymers are also of interest tomodify less refined wax where oil bleed out must be controlled such asscale wax. The use of high melt flow hSBS polymers to improve strength,toughness, and elasticity of less refined wax adds value to the systemeconomics as less refined wax is less expensive and more plentiful.

Specifically, an adhesive composition comprising: a blend of amorphouspoly-alpha-olefin, hSBS or hSBSS block copolymer, and tackifier; saidblock copolymer having a melt flow rate equal to or greater than 100g/10 min, said amorphous poly-alpha-olefin is present from about 30 toabout 80 wt. % of said composition, said block copolymer is present fromabout 10 to about 35 wt. % of said composition, and said tackifier ispresent from about 20 to about 60 wt. % of said composition.

Specifically, a film or melt blown article containing hSBS or hSBSShaving a low molecular weight in a range between 45,000 to 65,000, witha melt flow rate equal to or greater than 100 g/10 min has excellentstrength and elasticity, as defined by a film article having a tensilestrength >10 MPa and elongation >500% in addition to a hysteresis setafter 100% elongation of about 5%. The melt blown elastic article at 50g/m² (grams per square meter) has excellent elasticity, defined byhaving an ultimate tensile elongation >400%, with 100% hysteresisrecovered energy >80%, and permanent set <10%.

A melt blown fabric may further include at least one additional nonwovenlayer comprised of thermoplastic polymer comprising spunbond,bicomponent spunbond, melt blown, or a bonded-carded-web layer used inthe construction of an adsorbent personal hygiene product such as a babydiaper article, adult incontinence article, or feminine napkin article.Furthermore the non-woven laminate can be made more elastic via anactivation process such as tentering, drawing and ring rolls. Melt blownarticles may contain an additional component of high flow polyolefinhaving a melt flow rate >40 g/10 min, polyisobutylene, polybutene,thermoplastic polyurethane, thermoplastic copolyester, oil, styrenicblock copolymer with melt flow rate <100 g/10 min, and/or mid-block orend block resins, such as Oppera 100A, Regalrez 1126, or Kristalex 5140.

Specifically, a slush molding or rotational molding composition, such asis disclosed in EP Pat. No. 0733677 or WO Pat. No. 2011/092071 employs,styrenic block copolymer, wherein the molding composition has a meltindex in the range from 5 to 75, but examples disclose 40 to 89 g/10 minat 190° C. with 2.16 kg mass.

Specifically, an aqueous based emulsion of the styrenic block copolymerof the present invention (hSBS and or hSBSS) having the low melt flowrate and molecular weight described previously may be employed as acoating. The coating may optionally include functionalized styrenicblock copolymers of the invention, less than 20 wt. % organic solvent,and/or tackifying resin.

Either the solvent based or aqueous based coating, mentioned previously,may find utility by impregnating a fabric (woven or nonwoven) or felt.Likewise the coating may include a foaming agent and be incorporated infoamed articles.

Selectively hydrogenated styrenic block copolymers having a melt indexof >100 g/10 min are novel and find utility in at least all the areasmentioned above.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a graph of chopped fiberglass mat toughening shown by TotalImpact Energy in inch-pound force vs. hSBS basis weight in grams persquare meter, as tabulated in Table 1.

FIG. 2 is a photo of the test specimens associated with Tables 10 and11.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As used herein, unless otherwise noted, the term “molecular weights”refers to the true molecular weight in g/mol of the polymer or block ofthe copolymer. The molecular weights referred to in this specificationand claims can be measured with gel permeation chromatography (GPC)using polystyrene calibration standards, such as is done according toASTM 3536. GPC is a well-known method wherein polymers are separatedaccording to molecular size, the largest molecule eluting first. Thechromatograph is calibrated using commercially available polystyrenemolecular weight standards. The molecular weight of polymers measuredusing GPC so calibrated are styrene equivalent molecular weights, alsoknown as apparent molecular weights. The styrene equivalent molecularweight may be converted to true molecular weight when the styrenecontent of the polymer and the vinyl content of the diene segments areknown. The detector used is preferably a combination ultraviolet andrefractive index detector. The molecular weights expressed herein aremeasured at the peak of the GPC trace, converted to true molecularweights, and are commonly referred to as “peak molecular weights”. Whenexpressed as apparent molecular weights they are similarly determinedwith the exception that consideration of the block copolymer compositionand the subsequent conversion to true molecular weights is not done.

Starting materials for preparing the block copolymers of the presentinvention include the initial monomers. The alkenyl arene can beselected from styrene, alpha-methylstyrene, para-methylstyrene, vinyltoluene, vinylnaphthalene, and para-butyl styrene or mixtures thereof.Of these, styrene is most preferred and is commercially available, andrelatively inexpensive, from a variety of manufacturers.

The conjugated dienes for use herein are 1,3-butadiene and substitutedbutadienes such as isoprene, piperylene, 2,3-dimethyl-1,3-butadiene, and1-phenyl-1,3-butadiene, or mixtures thereof. Of these, 1,3-butadiene ismost preferred. As used herein, and in the claims, “butadiene” refersspecifically to “1,3-butadiene”.

Other important starting materials for anionic co-polymerizationsinclude one or more polymerization initiators. In the present inventionsuch include, for example, alkyl lithium compounds and otherorganolithium compounds such as s-butyllithium, n-butyllithium,t-butyllithium, amyllithium and the like, including di-initiators suchas the di-sec-butyl lithium adduct of m-diisopropenyl benzene. Othersuch di-initiators are disclosed in U.S. Pat. No. 6,492,469. Of thevarious polymerization initiators, s-butyllithium is preferred. Theinitiator can be used in the polymerization mixture (including monomersand solvent) in an amount calculated on the basis of one initiatormolecule per desired polymer chain. The lithium initiator process iswell known and is described in, for example, U.S. Pat. Nos. 4,039,593and Re. 27,145, which descriptions are incorporated herein by reference.

The solvent used as the polymerization vehicle may be any hydrocarbonthat does not react with the living anionic chain end of the formingpolymer, is easily handled in commercial polymerization units, andoffers the appropriate solubility characteristics for the productpolymer. For example, non-polar aliphatic hydrocarbons, which aregenerally lacking in ionizable hydrogens make particularly suitablesolvents. Frequently used are cyclic alkanes, such as cyclopentane,cyclohexane, cycloheptane, and cyclooctane, all of which are relativelynon-polar. Other suitable solvents will be known to one skilled in theart and can be selected to perform effectively in a given set of processconditions, with temperature being one of the major factors taken intoconsideration.

Preparation of radial (branched) polymers requires a post-polymerizationstep called “coupling”. It is possible to have either a branchedselectively hydrogenated block copolymer and/or a branched tailoredsoftening modifier. In the above radial formula for the selectivelyhydrogenated block copolymer, n is an integer of from 2 to about 30,preferably from about 2 to about 15, and X is the remnant or residue ofa coupling agent. A variety of coupling agents are known in the art andinclude, for example, dihalo alkanes, silicon halides, siloxanes,multifunctional epoxides, silica compounds, esters of monohydricalcohols with carboxylic acids, (e.g., dimethyl adipate) and epoxidizedoils. Star-shaped polymers are prepared with polyalkenyl coupling agentsas disclosed in, for example, U.S. Pat. Nos. 3,985,830; 4,391,949; and4,444,953; Canadian Pat. No. 716,645. Suitable polyalkenyl couplingagents include divinylbenzene, and preferably m-divinylbenzene.Preferred are tetra-alkoxysilanes such as tetra-ethoxysilane (TEOS) andtetra-methoxysilane, alkyl-trialkoxysilanes such as methyl-trimethoxysilane (MTMS), aliphatic diesters such as dimethyl adipate and diethyladipate, and diglycidyl aromatic epoxy compounds such as diglycidylethers deriving from the reaction of bis-phenol A and epichlorohydrin.

Coupling efficiency is of critical importance in the synthesis of blockcopolymers, which copolymers are prepared by a linking technology. In atypical anionic polymer synthesis, prior to the coupling reaction, theunlinked arm has only one hard segment (typically polystyrene). Two hardsegments are required in the block copolymer if it is to contribute tothe strength mechanism of the material. Uncoupled arms dilute thestrength forming network of a block copolymer that weakens the material.The very high coupling efficiency realized in the present invention iskey to making high strength, coupled, block copolymers.

Another important aspect of the present invention is to control themicrostructure or vinyl content of the conjugated diene in the B block.The term “vinyl” has been used to describe the polymer product that ismade when 1,3-butadiene is polymerized via a 1,2-addition mechanism. Theresult is a monosubstituted olefin group pendant to the polymerbackbone, a vinyl group. In the case of anionic polymerization ofisoprene, insertion of the isoprene via a 3,4-addition mechanism affordsa geminal dialkyl C═C moiety pendant to the polymer backbone. Theeffects of 3,4-addition polymerization of isoprene on the finalproperties of the block copolymer will be similar to those from1,2-addition of butadiene. When referring to the use of butadiene as theconjugated diene monomer, it is preferred that about 10 to 80 molpercent of the condensed butadiene units in the polymer block have a1,2-addition configuration. Preferably, from about 30 to about 80 molpercent of the condensed butadiene units should have 1,2-additionconfiguration. When referring to the use of isoprene as the conjugateddiene, it is preferred that about 5 to 80 mol percent of the condensedisoprene units in the block have 3,4-addition configuration. Polymermicrostructure (mode of addition of the conjugated diene) is effectivelycontrolled by addition of an ether, such as diethyl ether, a diethersuch as 1,2-diethoxypropane, or an amine as a microstructure modifier tothe diluent. Suitable ratios of microstructure modifier to lithiumpolymer chain end are disclosed and taught in U.S. Pat. No. Re. 27,145.

It is well known in the art to modify the polymerization of theconjugated diene block to control the vinyl content. Broadly, this canbe done by utilizing an organic polar compound such as ether, includingcyclic ethers, polyethers and thioethers or an amine including secondaryand tertiary amines. Both non-chelating and chelating polar compoundscan be used.

Among the polar compounds which may be added in accordance with the oneaspect of this invention are dimethyl ether, diethyl ether, ethyl methylether, ethyl propyl ether, dioxane, dibenzyl ether, diphenyl ether,dimethyl sulfide, diethyl sulfide, tetramethylene oxide(tetrahydrofuran), tripropyl amine, tributyl amine, trimethyl amine,triethyl amine, pyridine and quinoline and mixtures thereof.

In the present invention “chelating ether” means an ether having morethan one oxygen as exemplified by the formula R(OR′).sub.m (OR″).sub.oOR where each R is individually selected from 1 to 8, preferably 2 to 3,carbon atom alkyl radicals; R′ and R″ are individually selected from 1to 6, preferably 2 to 3, carbon atom alkylene radicals; and m and o areindependently selected integers of 1-3, preferably 1-2. Examples ofpreferred ethers include diethoxypropane, 1,2-dioxyethane (dioxo) and1,2-dimethyoxyethane (glyme). Other suitable materials include CH₃ OCH₂CH₂ OCH₂ CH₂ OCH₃ (C₆H₁₄O₃— diglyme) and CH₃CH₂ OCH₂ CH₂ OCH₂CH₂—OCH₂CH₃. “Chelating amine” means an amine having more than one nitrogen suchas N,N,N′,N′-tetramethylethylene diamine.

The amount of polar modifier is controlled in order to obtain thedesired vinyl content in the conjugated diene block. The polar modifieris used in an amount of at least 0.1 moles per mole of lithium compound,preferably 1-50, more preferably 2-25, moles of promoter per mole of thelithium compound. Alternatively, the concentration can be expressed inparts per million by weight based on the total weight of solvent andmonomer. Based on this criteria from 10 parts per million to about 1weight percent, preferably 100 parts per million to 2000 parts permillion are used. This can vary widely, however, since extremely smallamounts of some of the preferred modifiers are very effective. At theother extreme, particularly with less effective modifiers, the modifieritself can be the solvent. Again, these techniques are well known in theart, disclosed for instance in Winkler, U.S. Pat. No. 3,686,366 (Aug.22, 1972), Winkler, U.S. Pat. No. 3,700,748 (Oct. 24, 1972) and Koppeset al, U.S. Pat. No. 5,194,535 (Mar. 16, 1993), the disclosures of whichare hereby incorporated by reference.

Hydrogenation can be carried out via any of the several hydrogenation orselective hydrogenation processes known in the prior art. For example,such hydrogenation has been accomplished using methods such as thosetaught in, for example, U.S. Pat. Nos. 3,595,942; 3,634,549; 3,670,054;3,700,633; and Re. 27,145, the disclosures of which are incorporatedherein by reference. These methods operate to hydrogenate polymerscontaining aromatic or ethylenic unsaturation and are based uponoperation of a suitable catalyst. Such catalyst, or catalyst precursor,preferably comprises a Group VIII metal such as nickel or cobalt whichis combined with a suitable reducing agent such as an aluminum alkyl orhydride of a metal selected from Groups I-A, II-A and III-B of thePeriodic Table of the Elements, particularly lithium, magnesium oraluminum. This preparation can be accomplished in a suitable solvent ordiluent at a temperature from about 20° C. to about 80° C. Othercatalysts that are useful include titanium based catalyst systems.

The selectively hydrogenated controlled distributionstyrene-diene/styrene-styrene block copolymers applied in the presentinvention have been described in U.S. Pat. No. 7,169,848 to Bening etal. These block copolymers have mixed monomer rubbery blocks (conjugateddiene/mono alkenyl arene) which are made by the combination of a uniquecontrol for the monomer addition and the use of diethyl ether or othermodifiers as a component of the solvent (which will be referred to as“distribution agents”) which results in a certain characteristicdistribution of the two monomers (herein termed a “controlleddistribution” polymerization, i.e., a polymerization resulting in a“controlled distribution” structure), and also results in the presenceof certain mono alkenyl arene rich regions and certain conjugated dienerich regions in the polymer block. For purposes hereof, “controlleddistribution” is defined as referring to a molecular structure havingthe following attributes: (1) terminal regions adjacent to the monoalkenyl arene homopolymer (“A”) blocks that are rich in (i.e., having agreater than average amount of) conjugated diene units; (2) one or moreregions not adjacent to the A blocks that are rich in (i.e., having agreater than average amount of) mono alkenyl arene units; and (3) anoverall structure having relatively low blockiness. For the purposeshereof, “rich in” is defined as greater than the average amount,preferably greater than 5% the average amount. This relatively lowblockiness can be shown by either the presence of only a single glasstransition temperature (“Tg,”) intermediate between the Tg's of eithermonomer alone, when analyzed using differential scanning calorimetry(“DSC”) thermal methods or via mechanical methods, or as shown viaproton nuclear magnetic resonance (“H-NMR”) methods. The potential forblockiness can also be inferred from measurement of the UV-visibleabsorbance in a wavelength range suitable for the detection ofpolystyryllithium end groups during the polymerization of the B block. Asharp and substantial increase in this value is indicative of asubstantial increase in polystyryllithium chain ends. In this process,this will only occur if the conjugated diene concentration drops belowthe critical level to maintain controlled distribution polymerization.Any styrene monomer that is present at this point will add in a blockyfashion. The term “styrene blockiness”, as measured by those skilled inthe art using proton NMR, is defined to be the proportion of S units inthe polymer having two S nearest neighbors on the polymer chain. Thestyrene blockiness is determined after using H-1 NMR to measure twoexperimental quantities as follows:

First, the total number of styrene units (i.e. arbitrary instrumentunits which cancel out when ratioed) is determined by integrating thetotal styrene aromatic signal in the H-1 NMR spectrum from 7.5 to 6.2ppm and dividing this quantity by 5 to account for the 5 aromatichydrogens on each styrene aromatic ring.

Second, the blocky styrene units are determined by integrating thatportion of the aromatic signal in the H-1 NMR spectrum from the signalminimum between 6.88 and 6.80 to 6.2 ppm and dividing this quantity by 2to account for the two ortho hydrogens on each blocky styrene aromaticring. The assignment of this signal to the two ortho hydrogens on therings of those styrene units which have two styrene nearest neighborswas reported in F. A. Bovey, High Resolution NMR of Macromolecules(Academic Press, New York and London, 1972), Chapter 6. The styreneblockiness is simply the percentage of blocky styrene to total styreneunits:

Blocky %=100 times (Blocky Styrene Units/Total Styrene Units)

Expressed thus, Polymer-Bd-S—(S)_(n)—S-Bd-Polymer, where n is greaterthan zero is defined to be blocky styrene. For example, if n equals 8 inthe example above, then the blockiness index would be 80%. It ispreferred that the blockiness index be less than about 40. For somepolymers, having styrene contents of ten weight percent to forty weightpercent, it is preferred that the blockiness index be less than about10.

Hydrogenation can be carried out under such conditions that at leastabout 90% of the conjugated diene double bonds have been reduced, andbetween zero and 10% of the arene double bonds have been reduced.Preferred ranges are at least about 95% of the conjugated diene doublebonds reduced, and more preferably about 98% of the conjugated dienedouble bonds are reduced. Alternatively, it is possible to hydrogenatethe polymer such that aromatic unsaturation is also reduced beyond the10% level mentioned above. Such exhaustive hydrogenation is usuallyachieved at higher temperatures. In that case, the double bonds of boththe conjugated diene and arene may be reduced by 90% or more.

Once the hydrogenation is complete, it is preferable to extract thecatalyst by stirring with the polymer solution a relatively large amountof aqueous acid (preferably 20-30 percent by weight), at a volume ratioof about 0.5 parts aqueous acid to 1 part polymer solution. Suitableacids include phosphoric acid, sulfuric acid and organic acids. Thisstirring is continued at about 50° C. for about 30 to about 60 minuteswhile sparging with a mixture of oxygen in nitrogen. Care must beexercised in this step to avoid forming an explosive mixture of oxygenand hydrocarbons.

Examples of various fillers that can be employed are found in the1971-1972 Modern Plastics Encyclopedia, pages 240-247. A reinforcementmay be defined simply as the material that is added to a resinous matrixto improve the strength of the polymer. Most of these reinforcingmaterials are inorganic or organic products of high molecular weight.Various examples include calcium carbonate, talc, silica, clays, glassfibers, asbestos, boron fibers, carbon and graphite fibers, whiskers,quartz and silica fibers, ceramic fibers, metal fibers, natural organicfibers, and synthetic organic fibers. Especially preferred arereinforced polymer blends of the instant invention containing about 2 toabout 80 percent by weight calcium carbonate, based on the total weightof the resulting reinforced blend.

The polymer blends of the present invention may be compounded furtherwith other polymers, oils, fillers, reinforcements, antioxidants,stabilizers, fire retardants, antiblocking agents, lubricants and otherrubber and plastic compounding ingredients without departing from thescope of this invention.

Tackifying resins include polystyrene block compatible resins andmidblock compatible resins. The polystyrene block compatible resin maybe selected from the group of coumarone-indene resin, polyindene resin,poly(methyl indene) resin, polystyrene resin,vinyltoluene-alphamethylstyrene resin, alphamethylstyrene resin andpolyphenylene ether, in particular poly(2,6-dimethyl-1,4-phenyleneether). Such resins are e.g. sold under the trademarks “HERCURES”,“ENDEX”, “KRISTALEX”, “NEVCHEM” and “PICCOTEX”. Resins compatible withthe hydrogenated (mid) block may be selected from the group consistingof compatible C₅ hydrocarbon resins, hydrogenated C₅ hydrocarbon resins,styrenated C₅ resins, C₅/C₉ resins, styrenated terpene resins, fullyhydrogenated or partially hydrogenated C₉ hydrocarbon resins, rosinsesters, rosins derivatives and mixtures thereof. These resins are e.g.sold under the trademarks “REGALITE”, “REGALREZ”, “ESCOREZ” and “ARKON.The amount of tackifying resin employed varies from about 5 to about 100parts by weight per hundred parts by weight rubber, or block copolymer,preferably about 20 to about 50 parts by weight. Also, one may use botha polystyrene block compatible resin and a midblock compatible resin.

The novel hSBS or hSBSS block copolymer has a melt flow rate ≧100 g/10min at 230° C., and 2.16 kg mass (ASTM D-1238), a minimum linearmolecular weight of about 45,000 to about 65,000, a PSC of between about18 to about 45%, a vinyl content of about 65 to 80%, and a couplingefficiency of about 60 to about 97%, said styrenic block copolymer beingselectively hydrogenated styrene-butadiene-styrene (hSBS) or selectivelyhydrogenated controlled distribution styrene-butadiene/styrene-styrene(hSBSS). The novel hSBS or hSBSS is a styrenic block copolymer having astructure consistent with selectively hydrogenatedpoly(monoalkenylarene-diene-monoalkenylarene),poly(monoalkenylarene-diene)_(n)X, controlled distributionpoly(monoalkenylarene-diene/monoalkenylarene-monoalkenylarene), orpoly(monoalkenylarene-diene/monoalkenylarene)_(n)X. The monoalkenylarenemonomer is preferably selected from the group consisting of styrene,alpha-methylstyrene, para-methylstyrene, tertiary-butyl styrene, vinyltoluene and the like or mixtures thereof; of these styrene is the mostpreferred. The diene monomer can be any aliphatic conjugated dieneincluding 1,3-butadiene or substituted butadienes such as isoprene ormixtures thereof; of these 1,3-butadiene is the most preferred. As usedherein and in the claims, “butadiene” refers specifically to“1,3-butadiene”. The melt flow rate is achieved by hSBS or hSBSS whereineach styrene block has a peak molecular weight of between 5000 and 7000,and the total peak weight for either block copolymer is between 45,000to 65,000. The polymer, before hydrogenation, can be linear or radialhaving the respective S-D-S or (S-D)_(n)X structure where n is 2-3, S isstyrene, D is diene or diene/styrene, and X is the coupling agentresidue. The diene can be butadiene, isoprene, or mixtures thereof.Specifically the coupling agent could include but is not limited to Epon825, 862, 826, silanes like methyltrimethoxy silane, tetramethoxysilane, dimethyldimethoxy silane, and chlorosilanes.

The styrenic block copolymers of the present invention can also befunctionalized by the incorporation of grafted maleic anhydride, forexample, onto the back bone of the block copolymer. In the alternative,the block copolymers of the present invention can be functionalized in anumber of ways. One way is by treatment with an unsaturated monomerhaving one or more saturated groups or their derivatives such ascarboxylic acid groups and their salts, anhydrides, esters, imides,amides, or acid chloride groups. The preferred monomers to be graftedonto the block copolymers are maleic anhydride, maleic acid, fumaricacid, or their derivatives. See, U.S. Pat. Nos. 4,578,429 and 5,506,299.In another manner, the selectively hydrogenated block copolymer of thepresent invention may be functionalized by grafting silicon or boroncontaining compounds to the polymer as taught by U.S. Pat. No.4,882,384. In yet another manner, the block copolymer of the presentinvention may be reacted with an alkoxy-silane compound to formsilane-modified block copolymer. Also, the block copolymers of thepresent invention may be functionalized by grafting at least oneethylene oxide molecule to the polymer as taught by U.S. Pat. No.4,898,914, or reacting the polymer with carbon dioxide as taught by U.S.Pat. No. 4,970,265.

Example 1 High Melt Flow hSBS Polymer

hSBS: 201 kg Cyclohexane and 9.1 kg styrene were charged to an 80 galstainless steel reactor at about 50° C. 2428 mL of about 12 wt. %s-butyllithium were then charged to the reactor to initiatepolymerization. The styrene polymerization was allowed to proceed atabout 50° C. until completion and a sample was collected for GPC. Themolecular weight at this step was determined to be 4.8 kg/mole. Anadditional 0.38 kg of styrene was added and allowed to polymerize. GPCanalysis of this polymer indicated that the molecular weight was 5.0kg/mole. Butadiene was added at a rate of about 1 kg/min. Within lessthan a minute of starting the butadiene program, 198 grams of1,2-diethoxypropane were added and then the butadiene addition rate wasincreased to 1.5 kg/min. A total of 36.05 kg of butadiene was added, thetemperature was maintained between about 50° C. and 55° C., and thepolymerization was allowed to continue until completion. A samplecollected at the end of this step had a molecular weight of 26.0kg/mole, a vinyl content of 73.7% and a polystyrene content of 24.1% by¹H NMR. The S-B diblock polymer was then coupled by the addition of 114mL of methyl trimethoxysilane, resulting in a polymer in which 94% ofthe diblock chains are coupled, the majority (82%) being linear, and theremainder being primarily 3-arm radial species. 55 ml of methanol wereadded to ensure termination. This polymer was then hydrogenated to aresidual unsaturation of 0.12 meq olefin/g using a Co/Al catalyst (1.7:1Al:Co (mole/mole), about 22 PPM Co) at 700 psi hydrogen, 85° C. to forma selectively hydrogenated styrene-butadiene-styrene polymer; about 60kg of the total 125 kg of polymer solution was added in the initialbatch charge and the remainder was added at a rate as required tomaintain the reaction temperature in the desired range. The catalyst wasoxidized and extracted by contacting the cement with aqueous phosphoricacid while sparging with an N₂/O₂ gas blend; in addition, about 100 mLof caprylic acid was added. The cement was then neutralized by spargingwith ammonia, washed with deionized water and stabilized by the additionof Ethanox 330 (0.2 wt. % polymer basis) and Irgafos 168 (0.3 wt. %polymer basis). The resulting Inventive hSBS polymer had a melt flowrate of 220 g/10 min.

Application Examples of High Melt Flow hSBS Example 2 Fiberglass Matsand Scrim

The technology of the present invention is expected to provide impactresistance and enhanced toughness to composites containing fiberglassmats and scrims with significantly improved manufacturing and health,safety, and environmental aspects. The hSBS or hSBSS of the presentinvention having a melt flow rate ≧100 g/10 min has sufficiently highmolecular weight that it is not volatile and exhibits excellentelasticity and toughness while its high flow characteristics enableapplication as a melt blown fiber, fabric, or low basis weight film. Atleast 3 different processes can be envisioned to combine a tough,elastic high flow hSBS or hSBSS with a fiberglass mat or scrim.

1. The melt blown fibers could be co-blown when the fiberglass isproduced such that the tough, elastic fibers penetrate the thickness ofthe fiberglass mat.2. The film can be melt coated on top of a pre-existing fiberglass mator scrim.3. The melt blown fabric or film can be laminated to the fiberglass mator scrim.

In asphalt roofing applications, it is important that such roofs be ableto withstand hail damage. Thus it is desired to increase the impactresistance of the roofing article. Such roofing materials are compositescomprising at least one fiber glass mat and asphalt as the binder. Inthis example, the hSBS or hSBSS was produced as a low basis weight filmwhich was then laminated to a fiberglass mat. A surprisingly low basisweight of the styrenic block copolymer was required in order to achievea significant increase in the fiberglass mat's impact resistance. Thefollowing materials were used in this example.

Materials:

1. A 13.5 osy—ounces per square yard (˜450 g/m²—grams per square meter)chopped fiberglass mat was purchased from US Composites. This type ofmat is commonly used for mold, automotive, and boat buildingapplications. This mat typically requires 24 osy resin to providesufficient toughness.2. hSBS extruded film at 6.5 mil thickness which is ˜4.2 osy or 140g/m².

Experimental Conditions:

HSBS film was extruded on a Killion film extruder with temperaturesettings of 300-330-360-370° F. with the die set to 370° F.

Fiberglass mat samples were cut into 15 inch-wide sections. HSBS filmthicknesses having 140, 280, and 560 grams per square meter wereoverlaid on top of the fiberglass mat sections. The multi-layerconstruction was passed through a two roll laminator with the rolltemperature set to 350° F. 10 cm×10 cm squares were cut out of thelaminated fiberglass mat sections and baked at 450° F. for 90 secondswith no applied pressure.

The 10 cm×10 cm laminated fiberglass mat sections were tested in aDynatup Instrumented Impact Tester Model 8250 where a weight of 4.2 lbswas impacted into the sample at a velocity of 8400 in/min. The totalimpact force was measured by a load cell and the total impact energy wasreported in in-lbf. The impact test temperature was 23° C.

Surprisingly, a melt coating of hSBS applied at only 140 gsm results inan increase in the total impact energy by an order of magnitude from 2in-lbf to 20 in-lbf, see Table 1 and FIG. 1. This basis weight issignificantly lower than that of a reactive resin reported to providesufficient toughening. As the hSBS basis weight was increased in thelaminated fiberglass mat, the total impact energy continued to increasesuch that the combination of basis weight and impact resistance could betailored for specific applications. Generally laminated fiberglass matsof the present invention containing 50 to 1000 g/m² of the hSBS have anaverage impact energy of at least 2 times, preferably at least 3 timesmore compared to mats having no hSBS.

TABLE 1 hSBS basis AVG Total Impact ST DEV Total Sample wt, g/m² Energy,in-lbf Energy, in-lbf Fiberglass mat 0 2.0 0.8 control Fiberglass 1 14020.0 0.6 Fiberglass 2 280 28.6 4.0 Fiberglass 4 560 41.0 0.0

Fiberglass reinforced mats, combined with bitumen, fillers and surfacingmaterials, find employment in forming roofing shingles, roofingmembranes, insulation, sound mitigating articles, vibration dampingarticles, wind resistant articles, and geo-membranes having vegetativeroot growth resistance.

Thermoset composites containing fiberglass reinforced mats wherein saidthermoset is epoxy, urethane, polyester, acrylic, or a vinyl esterresin, find utility in composite articles intended for industrial,automotive, aerospace, or consumer applications such as boat hulls, carbody panels, turbine blades, hulls, sound mitigating articles, vibrationdamping articles, wind resistant articles, a geo-membrane having rootgrowth resistance, or a molding sheet.

Example 3 Low Viscosity Coatings

Low viscosity polymers (hSBS and hSBSS, as described above) are ofinterest in applications where VOC (volatile organic carbon)restrictions must be met. hSBS has a high melt flow rate (low viscosity)and was compared to other low viscosity polymers. It has been determinedthat only 4 VOC exempt solvents can be considered with hSBS, namelymethyl acetate, p-chlorobenzotriflouride, t-butyl acetate, and acetone.In areas where non-VOC restrictions are acceptable, any non-exemptsolvent (organic solvents that are not exempt) compatible with the lowviscosity polymer may be employed. Exemplary non-exempt solvents areAromatic 100 (a light aromatic naphtha), Aromatic 200 (a heavy aromaticnaphtha), xylene, toluene, and the like. Coatings comprising a blend ofsolvent (exempt, non-exempt, or a mixture thereof) and at least 40 wt. %of the styrenic block copolymer of the present invention of hSBS orhSBSS have a VOC content of <450 grams/liter, preferably <350grams/liter, and more preferably <250 grams/liter.

To determine the base line effect on viscosity for high melt flowpolymers, solutions were prepared in toluene and viscosity was measuredon a Brookfield viscometer at room temperature. Results were recorded incentipoise (cps). See Table 2. Results show that hSBS has the lowestviscosity compared to other SEBS (hydrogenatedstyrene-butadiene-styrene) polymers; G1643 has a melt flow rate of about19 g/10 min, G1726 has a melt flow rate of about 85 g/10 min, andPolymer 2 has a melt flow rate of about 43 g/10 min. All melt flow rateswere all measured at 230° C. and 2.16 kg mass.

TABLE 2 Toluene blends Solids 15% 25% 35% hSBS 16 88 422 G1643(SEBS) 38219 1285 Polymer 2 modified 59 412 2483 from USSN 13/243,533 G1726(SEBS)200 465

Effect of Xylene/PCBTF Blends on Polymer Viscosities

Solution viscosities of solvent blends comprising xylene and VOC exemptsolvent p-chlorobenzotriflouride (PCBTF) were measured. Solutions weremade with G1643 and hSBS polymers at 15, 20, and 25 wt % solids content.Results were measured in centipoise (cps). See Table 3. hSBS had thelowest viscosity compared to G1643. Viscosity increases as PCBTFdisplaces xylene in solutions.

TABLE 3 G1643 hSBS Polymer solids, % Xylene/PCBTF 15 20 25 15 20 25100/0  44 112 265 21 47 102 70/30 62 170 423 28 66 158 50/50 81 241 63835 91 221 30/70 110 352 986 46 132 334  0/100 165 790 2583 81 263 754

White Roof Coating Formulations

Elastomeric white roof coatings have more stringent requirements such asthe VOC must not be more than 250 g/liter. Elastomeric white roofcoating formulations were made to compare solution viscosities of G1643and hSBS polymers. Formulations were targeted to meet a VOC of 250grams/liter and all ingredient concentrations are listed in wt. %.Reduced viscosity has a significant effect on the application basisweight and drying time of the coating. HSBS resulted in a coatingformulation with suitable properties and lower viscosity than G1643. SeeTable 4. The requirements for elastomeric roof coatings are listed inASTM D6083. The viscosity requirement is 85-141 cps as measured by ASTMD562 Method A, Procedure A.

TABLE 4 Formulation 3-1 3-2 3-6 3-3 (G1643) (hSBS) G1643) (hSBS)Aromatic 100 13.81 14.3 14.1 14.7 Oxsol 100 PCBTF 32.59 32.12 31.7 31.1KratonG 1643 SEBS 21.42 18.1 Kraton hSBS 21.42 18.3 Kristalex 3070 LMW10.19 10.19 10.1 10.4 endblock resin Indopol H1900 — — 4.4 4.4 Irganox1010 0.32 0.31 0.31 0.32 Tinuvin 328/770 0.25 0.25 0.25 0.25 Fungicide0.42 0.42 0.41 0.42 TiO₂ 9.65 9.65 9.5 9.1 CaCO₃ 11.35 11.35 11.2 11.0Total 100 100 100 100 Calculated VOC, 250 250 250 250 g/literPCBTF/Aromatic 100 70/30 69/31 69/31 68/32 Solids/Solvent, wt. %53.3/46.7 53.3/46.7 53.9/46.1 53.9/46.1 Solids/Solvent, v % 50.0/50.050.7/49.3 50.6/49.4 51.5/48.5 poly/midblk/endblk 100/0/47.6 100/0/47.6100/24/57 100/24/57 resin Stormer Viscosity >141 137 >141 119

Aromatic 100 is the only solvent approved in Europe for white roofapplications.

The Stormer Viscosities >141 cps do not meet ASTM D562 Method A,Procedure A. However, hSBS meets this requirement.

Example 4 Adhesive Formulations

As noted previously, APO based adhesive formulations are low cost andlow performance. They are, however, sprayable which enablesapplicability to a wide range of articles. The performance of APOadhesive formulations can be upgraded to at least a mid-rangeperformance by blending with hSBS of the present invention. Theformulation is still sprayable, unlike many mid-range performancepolymers, including traditional SEBS based formulations based on SEBSpolymer with melt flow rates less than 100 g/10 min. Adhesiveformulations find utility in pressure sensitive adhesives, hot meltadhesives, construction adhesives, elastic adhesives, and the like.Generally these formulations contain styrenic block copolymers of thepresent invention, poly-alpha-olefin resins, tackifying resins, andoptional ingredients such as mineral oil, antioxidants, etc. Typicallythese compositions include poly-alpha-olefin present from about 30 toabout 80 wt. % of said composition, styrenic block copolymer hSBS and/orhSBSS present from about 10 to about 35 wt. % of said composition, andsaid tackifying resin present from about 20 to about 60 wt. % of saidcomposition.

Experimental Conditions:

Standard peel, tack, cohesion, and viscosity tests were carried out onthese formulations as described in the Test method manual for PressureSensitive Tapes from the Pressure Sensitive Tape Council (PSTC), thestandard FINAT test method for Pressure sensitive materials, the AFERAtest methods for Pressure Sensitive Adhesive Tapes, and the ASTM relatedmethods. Different testing surfaces have been used in determining theformulations' function in the application: chromed stainless steelplates (No. 304 “ss”) as recommended by the FINAT and Kraft paper.

Rolling Ball Tack (RBT) is the distance, expressed in centimeters, asteel ball rolls on the adhesive film with a standard initial velocity(Pressure Sensitive Tape Council Test No. 6; ASTM D3121-73). Smallnumbers indicate aggressive tack.

Loop Tack (LT) was determined using PSTC-5 and FTM 9 loop tack method.High numbers LT indicate aggressive tack.

180 Degree Peel Adhesion was determined by Pressure Sensitive TapeCouncil Method No. 1 and ASTM D3330-83. Large numbers indicate highstrength when peeling a test tape from a steel substrate.

The SAFT (shear adhesion failure temperature) was measured by 2.5×2.5 cmMylar to chromed ss plates with a 1 kg mass. The samples are placed inan oven and the temperature increased by 22° C./min SAFT measures thetemperature at which the lap shear assembly fails.

Holding Power (HP) is the time required to pull a standard area (2.5×1.3cm) of tape from a standard test surface (steel=ss) under a standardload (1 kg, 2 or 5 kg), in shear at 2° (Pressure Sensitive Tape CouncilMethod No. 7; ASTMD-3654-82). Long times indicate high adhesivestrength. Results are expressed in hours (h) or minutes (min). The typeof failure mode is expressed as adhesive failure (AF) or cohesivefailure (CF). This test can be carried out at room temperature (about23° C.) or at a more elevated temperature, depending on the test.

Preparation of Adhesive Formulations

No particular limitation is imposed on the preparation process of theadhesive compositions in the present invention. Therefore, any processsuch as, a mechanical mixing process making use of rolls, a Banburymixer or a Dalton kneader, a hot-melt process characterized in thatheating and mixing are conducted by using a melting kettle equipped witha stirrer, a high shear Z-blade mixer, a single- or twin-screw extruder,a solvent process in which the compounding components are poured in asuitable solvent and stirred, thereby obtaining an intimate solution ofthe pressure sensitive adhesive composition may be used.

The test formulations shown in Table 5 were hot melt mixed in a highshear sigma blade mixer that was blanketed with nitrogen. Typical orderof addition was polymer combined with stabilizer, then resin followed byaddition of oil. Mixing time averaged about one hour for the preparationof the homogeneous adhesive. Samples were then coated on 4 mil Mylar®film as a hot melt drawn down with a heated doctor blade to the averagefilm thicknesses give in Table 5. General test results are reported inTable 6. Hot melt test results are reported in Table 7.

TABLE 5 Test Formulation Composition Formulations wt % HMA1- hSBS HMA2HMA3 HMA4 HMA5 hSBS 16.5 G1643 (SEBS) 16.5 G1657 (SEBS) 16.5 D1155 (SBS)20 Rextac 2730 APAO 50 50 50 60 Eastotac H-100W 33.5 33.5 33.5 40 ResinDrakeol 34 20 Regalite S5100 60 Resin Total 100 100 100 100 100 Irganox1010 0.5 0.5 0.5 0.5 0.5 Appearance after smooth & smooth smooth smoothsmooth & mixing waxy yellow Average Film 50 55 60 50 55 Thickness (mil)

TABLE 6 Testing Results Appearance of melt smooth smooth grainy, meltsmooth smooth coated test samples fractured translucent translucenttranslucent clear yellow 180° Peel 3.7 4.4 2.9 0.8 8.5 Strength, pliComment adhesive adhesive cohesive did not adhere to cohesive failurefailure failure on steel Mylar. Adhesive failure to steel failure tosteel SAFT, ° C. 75 77 66 No tack 62 Holding power to >9000 >9000884/221 No tack 2052/1543 steel, min Loop tack, lbf 0.46 0.52 0.59 0.1210.4 Rolling ball tack, cm >30 >30 >30 >30 >30 After 200° F./7 day +250° C./2 day aging appearance (1 layer, smooth smooth smooth smoothsmooth 2 layers, grainy) color white white white white yellow

TABLE 7 Hot Melt Viscosity Results of the Test Results HMA1-hSBS HMA2HMA3 HMA4 HMA5 Viscosity at 4,125 6,900 10,030 1,750 1,325 350° F.Viscosity at 12,300 23,980 NM** 4,200 2,000 300° F. Viscosity at NM NMNM  10,050 17,800 250° F. *Brookfield Viscometer, Spindle 27, units incentipoises (cps) **NM = not measured due to already excessive viscosity

What is particularly useful for the hSBS application of sprayable hotmelt adhesives for non-woven construction is: (1) saturated polymerbackbone for thermal and color stability; (2) an adhesive failuremechanism; and (3) hot melt viscosity under 10,000 cps at 350° F.(typical spray application temperature) that enables acceptable sprayperformance. The control formulation consisting of the APO only (HMA4)has desirable low viscosity, and a saturated backbone but exhibitsunacceptably poor adhesion properties, i.e. almost no measureable tackor peel. The adhesive formulation of HMA4 adhered poorly to both theMylar® (polyester) and stainless steel substrates.

The data reveals that adding 16.5 wt. % of the block copolymer hSBS in ablend with APO affords low hot melt viscosity along with a reasonablebalance of adhesive properties. Only the formulations HMA1 and HMA2 wereobserved to fail adhesively which is the preferable failure mechanismfor non-woven construction adhesives.

The comparison formulation using SBS in HMA5 has the issue of colorstability and long term aging due to the unsaturated polybutadienerubber phase. This type of industry standard formulation using SBS inHMA5 (20% polymer, 60% resin, 20% oil) has low polymer content (foreconomy and low melt viscosity) and this negatively affects the failuremechanism of the adhesive.

Example 5 Film and Nonwoven Examples for Personal Hygiene Applications

Table 8 demonstrates that film made from the high melt flow SEBS(Inventive hSBS) has equivalent or better mechanical properties to filmmade from lower melt flow hSBS polymer formulations (Comparative 1 and2). Melt flow rates measured at 230° C. and 2.16 kg for MD6705 andMD6717 were 48 g/10 min and 55 g/10 min respectively. The recoveredenergy for Example 3 is 90% and the tensile set is 5%, indicatingexceptional elasticity for such a low molecular weight polymer. Inaddition, Table 8 shows that the high melt flow SEBS has excellentelasticity, up to 300% elongation at break. Good elasticity at highelongation, or strain, is also an indicator that the stress relaxationshould be low. Low stress relaxation results in a better fit versus timefor the elastic components in an absorbent personal hygiene garment orarticle such as a diaper.

Table 9 is a comparison of mechanical properties for a melt blown fabricmade from the high melt flow polymer (Inventive hSBS) to typical filmsused in personal hygiene applications at similar basis weights(Comparative 3 and 4). Because the basis weights are similar and all ofthe tested samples were the same width, force can be used as anindicator of strength and modulus at various strains. Table 9demonstrates that the Inventive hSBS fabric, in the machine direction,has equivalent or better 100% and 300% modulus and 100% and 300%hysteresis performance to Comparative 3 and 4 in the cross direction. Inaddition, the inventive hSBS fabric has equivalent or better performance(modulus and hysteresis) than Comparative 4 in machine direction. Theelongation at break and tensile strength at break are significantlylower for the Inventive hSBS fabric when compared to the filmcomparatives because the films can strain harden while the melt blownfabric is inherently limited by its structure. Consequently, since mostcommercial personal hygiene applications do not require strains muchhigher than 300%, the Inventive hSBS fabric demonstrates that anultra-high melt flow hSBS could perform well in personal hygiene elasticcomponents.

The mechanical properties are measured in the cross direction(perpendicular to the extrusion direction). Hysteresis is measured at100% elongation. Comparative 1 (MD6705) is a compound made with an 18MFR high vinyl SEBS. Comparative 2 (MD6717) is also a compound made withthe same 18 MFR SEBS but it also contains a high melt flow polyolefin.The inventive hSBS has a melt flow rate of 220 g/10 min. Comparative 3is a typical personal hygiene elastic film compound made with arelatively high molecular weight and low MFR hSBS (Kraton G).Comparative 4 is a film made from a typical personal hygiene SIS polymer(D1114).

TABLE 8 Cast Film Mechanical Properties MFR Recovered (230° C./ TensileElong. Energy Polymer/ 2.16 kg), Strength, at 1^(st) Hysteresis Propertyg/10 min MPa Break, % cycle, % Set, % Comparative 50 11 700 90 5 1(MD6705) Comparative 53 13 820 56 9 2 (MD6717) Inventive 220 11 750 90(83*) 5 (9*) hSBS *Hysteresis properties at 300% elongation.

TABLE 9 Melt Blown Fabric Mechanical Properties Comparative 4 InventiveComparative 3 (Kraton ™ hSBS (Typical D1114) Melt Elastic Film SIS BlownFabric* Kraton ™ G) Polymer Film Test (50 g/m²) (54 g/m²) (62 g/m²) FilmDirection MD CD MD CD MD CD 100% Mod (N) 0.18 0.09 0.27 0.13 0.09 0.09300% Mod (N) 0.5 0.13 0.8 0.3 0.18 0.13 Tensile (N) 0.7 0.18 5.8 4.0 43.6 Elongation to 450 530 830 810 1300 1300 Break (%) 100% 6.8 NA 4.54.8 7.2 7.7 Hysteresis Tensile Set (%) 100% 84 NA 90 90 90 90 HysteresisRecovered Energy (%) 300% 11 NA 9 6.5 13 15 Hysteresis Tensile Set (%)300% 73 NA 73 84 95 94 Hysteresis Recovered Energy (%) *The Example 4melt blown nonwoven fabric was made on a 5 inch wide melt blown line.

Example 6 Slush & Rotational Molding Example

Compounds based on inventive polymer hSBS show improved melt propertieswhen used in low shear processes such slush molding and rotationalmolding processes. Typical formulations of slush molding and rotationalmolding compounds may be seen in Table 10.

TABLE 10 Formulation 100 104 Ingredient % lbs % lbs Polymer 2 modified60.1 30.0 from USSN 13/243,533 Inventive hSBS 60.1 30.0 poly-1-butene13.3 6.7 13.3 6.7 Polypropylene 9.5 4.7 9.5 4.7 Aliphatic Oil 8.5 4.28.5 4.2 Plastomer 4.1 2.1 4.1 2.1 Slip Additive 3.9 2.0 3.9 2.0Antioxidant 0.39 0.20 0.39 0.20 UV absorber 0.20 0.10 0.20 0.10 Total100.0 50.0 100.0 50.0 Modifed Polymer 2 has a polystyrene end block molwt. of 7.2 kg/mol and a total apparent mol wt. of 127 kg/mol, with a MFRof about 43 g/10 min at 230° C. and 2.16 kg/mass.

Manufacture of these compounds were performed on standard plasticcompounding equipment such as a co-rotating twin screw extruder equippedwith underwater pelletizing apparatus familiar to one skilled in theart. Extruder barrel zone temperatures increased from 160° C. to 210° C.down the length of the barrel and the adapter and die temperatures were210° C. to 230° C. The melt temperatures of the described compounds were210° C. and 240° C. for Formulations 100 and 104, respectively.Evaluation of the suitability for low shear processes such as slushmolding or rotational molding was established by measuring flow at zeroshear rate on compression molded test samples. Test specimens were diecut from a compression molded plaques that were nominally 3 mm inthickness. See FIG. 2. The height and width of the sample was measuredat its center point. The specimen was then placed onto a flat plate andput into a preheated convection oven at 230° C. for 90 seconds. When itwas removed from the oven, the specimen was allowed to cool forapproximately 5 minutes and the sample thickness was re-measured againat its center point. (REF) is the non-heated reference specimen.Formulation (100) reference specimen is subjected to melt test based onprior art. Formulation (104) is the inventive formulation incorporatinghSBS.

Afterwards the height and width of the samples was measured again and a% Melt is calculated according to Eq. 1, and the results are in Table11.

$\begin{matrix}{{\% \mspace{14mu} {Melt}} = {\frac{{Thickness}_{initial} - {Thickness}_{initial}}{{Thickness}_{initial}} \times 100}} & {{Eq}.\mspace{14mu} 1}\end{matrix}$

TABLE 11 Melt Performance Initial Initial Final Final Melt ThicknessWidth Thickness Width Time % Compound (mm) (mm) (mm) (mm) (s) Melt 1003.11 2.42 1.53 5.93 90 51% 100 3.11 2.46 1.52 5.22 90 51% 104 3.17 2.441.18 7.61 90 63% 104 3.12 2.43 1.09 8.26 90 65%

Tabulated results and visual inspection of the test specimens showedthat the example compound containing the Inventive hSBS (104) exhibits ahigher flow under zero shear rate conditions and therefore a higher %melt as calculated according to Eq. 1.

Thus it is apparent that there has been provided, in accordance with theinvention several applications for the use of the unique and novel hSBSor hSBSS block copolymer that has a MFR of at least 100 g/10 min thatfully satisfies the objects, aims, and advantages set forth above. Whilethe invention has been described in conjunction with specificembodiments thereof, it is evident that many alternatives,modifications, and variations will be apparent to those skilled in theart in light of the foregoing description. Accordingly it is intended toembrace all such alternatives, modifications and variations as fallwithin the spirit and broad scope of the appended claims.

What is claimed is:
 1. A aqueous based emulsion of styrenic blockcopolymer having a melt flow rate greater than 100 g/10 min at 230° C.,and 2.16 kg mass, said styrenic block copolymer being hydrogenatedstyrene-butadiene-styrene or selectively hydrogenated controlleddistribution styrene-butadiene/styrene-styrene.
 2. The aqueous basedemulsion of claim 1, wherein said styrenic block copolymer includesgrafted maleic anhydride.
 3. The aqueous based emulsion of claim 1,containing less than 20 wt. % organic solvent.
 4. The aqueous basedemulsion of claim 1, wherein said emulsion includes a tackifier and isemployed as a coating.
 5. The aqueous based emulsion of claim 4, whereinsaid tackifier is compatible with polystyrene.
 6. The aqueous basedemulsion of claim 4, wherein said tackifier is compatible withpolybutadiene.
 7. The aqueous based emulsion of claim 4, wherein saidtackifier is present from 5 to 100 parts by wt. based on 100 parts bywt. styrenic block copolymer.
 8. The aqueous based emulsion of claim 1,wherein said styrenic block copolymer has a minimum peak mol. wt. of45,000, a polystyrene content of 18-45%, a vinyl content of 65-80%, anda coupling efficiency of 60-97%.
 9. The aqueous based emulsion of claim1, wherein said butadiene in said styrenic block copolymer ishydrogenated at least 90%.